Keeping beer chilled from keg to tap

[Stan] was putting together his nano-brewery, and while waiting for his beer to finish fermenting, he decided to work on the storage portion of his project. He built a kegerator to store his forthcoming brews but realized that since it was about 10 feet away from his tap tower, the beer was becoming unacceptably warm and frothy in transit.

In commercial tap systems, a separate line of chilled propylene glycol is bundled with the beer lines, keeping it cool as it travels from keg to tap. [Stan] decided to replicate this setup, and after three different iterations, he nailed it.

His first two attempts involved keeping the cooling solution inside of the kegerator, but he found that either the pumps added too much heat to the solution, or that the kegerator was running at nearly a 100% duty cycle. Scrapping any sort of kegerator-based cooling, he decided to build a separate cooling unit with a dehumidifier he had sitting around. After fitting the unit into a cooler and filling it with solution, he found it to cool so well it turned the propylene glycol solution to slush!

Check out his site for more details on his cooling setup – if you are in the business of homebrew, you will be glad you did.

Also, I can almost guarantee you that re-purposed dehumidifier was soldered with lead and the copper also probably contains unhealthy amounts of lead. As long as the beer stays in stainless steel lines, it is probably fine but something to be aware of.

Ever heard of a chill plate? It’s essentially a piece of aluminum with a path for your beer to pass through; put it in a cooler full of ice and it’ll dispense cold beer till the ice/water gets too warm which is usually long before you are done. Yeah, I know this isn’t very “hackable” but it is far more energy efficient and you could always learn to cast your own aluminum, etc. and make your own.

We used to have a pop machine in the house years ago. The carbonator and syrup was in the basement and heads were on the first floor. We took an old AC unit and cut off the cold side and replaced it with about 60 ft of 1/4″ copper pipe with a two elbows at the top to make a u-turn. Then we wrapped the supply lines and copper pipe in insulation. It took a couple of weeks to get the temps right, but it kept everything nice and cool.

**btw, don’t do this without a reclaimer. If you wanna do this, just call a heating/ac guy and ask them if they can do the freon part of it (reclaim and filling).

I wonder if something like an automotive heater core (unused, of course) is food-safe? If you ran pure ethanol through it for a while to dissolve any manufacturing oils, then flushed it with water, I bet the insides would be clean enough to drink from. Put it in a cooler of ice water and you’ve got an instant liquid chiller.

I suppose it might rust, though. What are heater core internal lines made of?

I wonder if something like an automotive heater core (unused, of course) is food-safe? If you ran pure ethanol through it for a while to dissolve any manufacturing oils, then flushed it with water, I bet the insides would be clean enough to drink from. Put it in a cooler of ice water and you’ve got an instant liquid chiller.

Do not do this. Ever. Unless you are absolutely sure the solder they use is lead free. *Some* modern cars no longer use lead. Most do. In the braze and in the copper. Many of them are also painted and you have no idea what went into that paint. You also have no idea if they used ethylene glycol to test the lines with. You can probably mostly clean that out but the lead? Nope. There is a very good reason why companies use stainless steel to brew with, mix pharmaceuticals with and make food with. I love creative hacks but please start with the right materials for food contact items, please.

“Before you say”Pressurize it!” the head pressure of that much CO2 will give you an unpleasantly large head.”

Could you pressurize it with filtered oil free air in a 5 gallon corny “pony” keg? Peristaltic pumps generally have fairly low head. *Probably* enough to up 8 – 15 feet no problem but you would want to double check.

Pump curves in feet of head can be converted to pressure – psi – by the expression:

p = 0.434 * h * SG

where

p = pressure (psi)

h = head (ft)

SG = specific gravity

As long as you can generate about 6 or 7 psi then you should be fine, just keep in mind the pressure the Co2 can create – most peristaltic pump lines are good for maybe 50 psi?

Good idea- but air (primarily dissolved oxygen) will stale the beer unless you can drink 5gal in a day or two. Same concept of pumping up a keg with an air pump- next day it already starts to taste a little funky. I need to keep the CO2 partial pressure at around 10psi to maintain the carbonation levels I prefer for my style of beer, but I can handle much higher hydrostatic pressure as long as the CO2 doesn’t come out of solution in the line. If I keep the line cool I don’t think it will be an issue (I’m not sure here- haven’t tried it yet). Thanks for the line advice- off to mcmaster carr for a price check!

I wish he would have posted pictures of the trunk line. The best method (IMO) for a trunk line would be probably a 1-1.25″ ID copper pipe, with the beer lines inside it. It would have sealed ends with barbs and the glycol solution running through it. Similar to a chemistry type condenser setup.

If the beer lines are steel, this would result in a very efficient method for chilling the beer in the lines.

Does anyone know how the storage temperature of the keg affects the shelf-life of the beer? I can’t seem to find a chart comparing the shelf lives relative to different types of pressurization and room temp v. cold storage.

from personal experiance ( i worked as a bar manger/supervisor for some years) you should never use straight CO2. usally a 80/20 mix of CO2/nitrogen is used this helps to keep head size down while still keeping presure in the lines (most pubs/bars in the uk have there cellers in basements)

For a pump to move the beer up floors, you can use SHURflo 2088-492-444 Park Model Fresh Water Pump. It’s food grade, made to pump potable water. It’s a workhorse, used on RVs and food trucks. This specific model is 115v AC, so you don’t have to worry about a DC converter. It’s also an on demand pump, so you don’t need to worry about a switch.